Slow94Formula

iTrader: (18)

Looking at doing a cam swap and making a list of things I need to buy. When I look for a timing chain this is all that shows up: http://sdparts.com/details/gm-perfor...parts/12370835

Do I have to get that and convert my car to a vented opti and all that BS in order to get a new timing chain? It looks like to convert to a vented opti it is going to cost about $500 everything... If I really do have to convert it to a vented style is there such a kit that someone sells that includes everything necessary?

Thanks in advance! And yes I did try lol.

Zlow28

iTrader: (11)

These are the OE parts number.

stock timing chain= 10128485
cam sprocket= 10128349
crank sprocket= 10128346

For a 94 lt1.

RamAir95TA

iTrader: (2)

Converting to a vented opti is more than just easy bolt-on parts. You also need a different camshaft.

Or, you could pick up the MSD cap and rotor kit that can make your Gen I opti vented.

shbox

If you are going to run a non-vented opti, you are pretty much stuck with a stock timing set, because the opti requires the splined cam gear to turn it. If you go with a vented opti conversion, your options increase and if you add an electric water pump, your options will include any SBC roller cammed set.

Slow94Formula

iTrader: (18)

The plan is to do an Ai cam while all of this is apart. What aspects does that change for me?

shbox

It means you have the part of buying a cam covered for the vented opti conversion.

Pre-written blurb:

If you want to change to a vented from non-vented, you have to do many things. It may not be cost effective unless you are doing a cam swap at the same time.

Besides the optispark itself (GM p/n 1104032), you need:

• 95 or later timing cover [1995 front cover (includes round seals) GM p/n 12552426-now discontinued]
• late model or aftermarket cam (or have your cam modified by drilling the hole in the front to the proper size [.500"dia. X 1.0625" deep] and a longer dowel pin added (pin needs to protrude ~.650" from the nose of the cam)
• 95 and later optispark electrical harness GM p/n 12130319 (cheaper aftermarket harnesses available)
• optispark vacuum harness GM p/n 12555323
• vacuum fitting [GM p/n 14082470] or "tee" to provide vacuum for the opti
• 95 or later timing set components (or at least the cam gear) cam gear (GM p/n 10206039), crank gear (GM p/n 10128346), chain (GM p/n 10128485)
• timing cover gasket GM p/n 10128293
• water pump gaskets [2] GM p/n 10128343
• intake manifold gaskets if you are pulling the cam GM p/n 12524653

Or you can put an MSD cap/rotor kit on it and essentially have a vented opti. They come with their own similar venting system.

Slow94Formula

iTrader: (18)

Would the MSD be a good idea instead of the ACdelco one? Just trying to weigh my options and want to know others opinions.

shbox

For a vented opti, I recommend the GM one over the MSD.

Slow94Formula

iTrader: (18)

Ok. Thanks for the help!

Slow94Formula

iTrader: (18)

What options do I have for timing chains besides the GM one? Do I have to get the GM timing chain set in order to swap to a vented opti or can I buy something cheaper instead? (like this: http://www.summitracing.com/parts/LUN-93094/ )

defaultexistence

iTrader: (11)

^^^ yes but u then must run an electric water pump, see the top chain gear in an lt1'has a second gear behind the chain that drives the water pump gear.. That one does not

guppymech

iTrader: (7)

^^^^^

Just last week I bought the full GM timing set from gmpartseast and it cost $106 without shipping. Gmpartseast charges actual shipping.
I'll take OEM over aftermarket anytime.

defaultexistence

iTrader: (11)

I'm looking at this one http://m.summitracing.com/parts/NAL-12371043 for less.. I also will run an EWP though ...

Slow94Formula

iTrader: (18)

Can I purchase that and run it with the vented opti or is that a 1994 setup?

I know I am kind of all over the place, but I think what I would like to do is:
1. Run a factory style water pump (not electric)
2. Run a vented opti
3. Find the best deal on a timing chain possible (of course)

My opti died this weekend so I am going to go ahead and just put a vented setup in it... I guess I have plenty of time now. Haha

defaultexistence

iTrader: (11)

Did u miss the part where I said " you must run an electric pump" with either set listed above..?

Slow94Formula

iTrader: (18)

Yes I did... Damnit. So, what are people running for an electric water pump?

defaultexistence

iTrader: (11)

The CSR ... Go to eBay and type " lt1 water" and u'll see em.. Grab a part number if u Wana buy it from summit... Search the
Topic here...